Radio frequency (RF) energy is commonly used to treat patients who fail to respond to other methods of treatment. RF treatment can be used in pain management, neurosurgery, cardiac surgery, and in the treatment of cancer. The method involves applying to tissue a radio frequency electric field, using commercially available instruments, such as the OWL RF Lesion Generators manufactured by Diros Technology Inc. of Markham, Ontario, Canada. Both the heat and the electromagnetic field produced can have a biological effect on tissue. The energy can be used to stimulate, ablate or treat tissue.
Usually in RF treatment, electrodes are inserted into an insulated cannula that typically has a sharp, beveled, exposed bare tip so that the cannula may penetrate tissue, enter the body, and be guided (usually using a fluoroscope) toward tissue such as a neural structure or cardiac structure. The same cannula that accepts the electrode can also be used to deliver an anesthetic liquid, or a diagnostic localization agent to the target structure or tissue in the body, but this can only be done when the electrode is not inserted into the cannula. Thus two physical devices are required, one being the electrode structure, and the other being the cannula. The need to purchase, sterilize and use two separate devices adds complexity and cost to surgical procedures.